Dotson NM, Salazar RF, Gray CM (2014). Fronto-parietal correlation dynamics reveal interplay between integration and segregation during visual working memory. J Neuroscience, 34(41):13600-13.

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Abstract

Working memory requires large-scale cooperation among widespread cortical and subcortical brain regions. Importantly, these processes must achieve an appropriate balance between functional integration and segregation, which are thought to be mediated by task-dependent spatiotemporal patterns of correlated activity. Here, we used cross-correlation analysis to estimate the incidence, magnitude, and relative phase angle of temporally correlated activity from simultaneous local field potential recordings in a network of prefrontal and posterior parietal cortical areas in monkeys performing an oculomotor, delayed match-to-sample task. We found long-range intraparietal and frontoparietal correlations that display a bimodal distribution of relative phase values, centered near 0° and 180°, suggesting a possible basis for functional segregation among distributed networks. Both short- and long-range correlations display striking task-dependent transitions in strength and relative phase, indicating that cognitive events are accompanied by robust changes in the pattern of temporal coordination across the frontoparietal network.

Schlegel A, Kohler P, Fogelson S, Alexander S, Tse PU (2013). Network structure and dynamics of the mental workspace...

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Schlegel A, Kohler P, Fogelson S, Alexander S, Tse PU (2013). Network structure and dynamics of the mental workspace. Proceedings of the National Academy of Sciences, 110(40):16277-82.
[ DOI: 10.1073/pnas.1311149110. ]

 

Abstract

The conscious manipulation of mental representations is central to many creative and uniquely human abilities. How does the human brain mediate such flexible mental operations? Here, multivariate pattern analysis of functional MRI data reveals a widespread neural network that performs specific mental manipulations on the contents of visual imagery. Evolving patterns of neural activity within this mental workspace track the sequence of informational transformations carried out by these manipulations. The network switches between distinct connectivity profiles as representations are maintained or manipulated.